Systems and methods for making and using enhanced electrodes for electrical stimulation systems

ABSTRACT

A lead assembly for providing electrical stimulation of patient tissue includes at least one elongated lead body, each of the at least one lead bodies having a distal end and a proximal end. A plurality of electrodes are disposed at the distal end of the at least one lead body, each of the electrodes having an outer surface. A plurality of dimples are defined along the outer surface of at least one of the plurality of electrodes, the plurality of dimples configured and arranged to provide a larger surface area for the at least one dimpled electrode than that of a similarly-sized electrode with a flat outer surface. A plurality of terminal are disposed at the proximal end of the at least one lead body. A plurality of conductive wires couple each of the plurality of electrodes to at least one of the plurality of terminals.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.13/220,037 filed Aug. 29, 2011, now U.S. Pat. No. 8,504,171, whichclaims the benefit under 35 U.S.C. §119(e) of U.S. Provisional PatentApplication Ser. No. 61/378,773 filed on Aug. 31, 2010, all of which areincorporated herein by reference.

FIELD

The present invention is directed to the area of implantable electricalstimulation systems and methods of making and using the systems. Thepresent invention is also directed to implantable electrical stimulationleads that include electrodes with enhanced outer surfaces, as well asmethods of making and using the electrical stimulation leads,electrodes, and electrical stimulation systems.

BACKGROUND

Implantable electrical stimulation systems have proven therapeutic in avariety of diseases and disorders. For example, spinal cord stimulationsystems have been used as a therapeutic modality for the treatment ofchronic pain syndromes. Peripheral nerve stimulation has been used totreat chronic pain syndrome and incontinence, with a number of otherapplications under investigation. Deep brain stimulation can be usefulfor treating a variety of conditions including, for example, Parkinson'sdisease, dystonia, essential tremor, chronic pain, Huntington's Disease,levodopa-induced dyskinesias and rigidity, bradykinesia, epilepsy andseizures, eating disorders, and mood disorders. Functional electricalstimulation systems have been applied to restore some functionality toparalyzed extremities in spinal cord injury patients.

Stimulators have been developed to provide therapy for a variety oftreatments. A stimulator can include a control module (with a pulsegenerator), one or more leads, and an array of stimulator electrodes oneach lead. The stimulator electrodes are in contact with or near thenerves, muscles, or other tissue to be stimulated. The pulse generatorin the control module generates electrical pulses that are delivered bythe electrodes to body tissue.

BRIEF SUMMARY

In one embodiment, a lead assembly for providing electrical stimulationof patient tissue includes at least one elongated lead body, each of theat least one lead bodies having a distal end and a proximal end. Aplurality of electrodes are disposed at the distal end of the at leastone lead body, each of the electrodes having an outer surface. Aplurality of dimples are defined along the outer surface of at least oneof the plurality of electrodes, the plurality of dimples configured andarranged to provide a larger surface area for the at least one dimpledelectrode than that of a similarly-sized electrode with a flat outersurface. A plurality of terminal are disposed at the proximal end of theat least one lead body. A plurality of conductive wires couple each ofthe plurality of electrodes to at least one of the plurality ofterminals.

In another embodiment, a medical lead for providing electricalstimulation of patient tissue includes an elongated lead body having adistal end and a proximal end. A plurality of electrodes are disposed atthe distal end of the lead body, each of the plurality of electrodeshaving a width and an outer surface. At least one of the electrodesdefines a plurality of grooves along the outer surface that extendnon-linearly along the width of the electrode such that the grooves forma curved line. A plurality of terminals are disposed at the proximal endof the lead body. A plurality of conductive wires couple each of theplurality of electrodes to at least one of the plurality of terminals.

In yet another embodiment, an electrical stimulation lead for providingelectrical stimulation of patient tissue includes an elongated lead bodyhaving a distal end and a proximal end. A plurality of electrodes aredisposed at the distal end of the lead body. Each of the plurality ofelectrodes has an outer surface. At least some of the electrodes aresegmented electrodes that extend around a lateral circumference of thelead body. At least one of the segmented electrodes defines a surfacetexture defined in the outer surface of the segmented electrode, thesurface texture configured and arranged to provide a larger surface areafor the at least one dimpled electrode than that of a similarly-sizedelectrode with a flat outer surface. A plurality of terminals aredisposed at the proximal end of the lead body. A plurality of conductivewires couple each of the plurality of electrodes to at least one of theplurality of terminals.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present invention aredescribed with reference to the following drawings. In the drawings,like reference numerals refer to like parts throughout the variousfigures unless otherwise specified.

For a better understanding of the present invention, reference will bemade to the following Detailed Description, which is to be read inassociation with the accompanying drawings, wherein:

FIG. 1 is a schematic view of one embodiment of an electricalstimulation system that includes a paddle body coupled to a controlmodule via lead bodies, according to the invention;

FIG. 2 is a schematic view of another embodiment of an electricalstimulation system that includes a percutaneous lead body coupled to acontrol module via a lead body, according to the invention;

FIG. 3A is a schematic view of one embodiment of a plurality ofconnector assemblies disposed in the control module of FIG. 1, theconnector assemblies configured and arranged to receive the proximalportions of the lead bodies of FIG. 1, according to the invention;

FIG. 3B is a schematic view of one embodiment of a connector assemblydisposed in the control module of FIG. 2, the connector assemblyconfigured and arranged to receive the proximal portion of one of thelead body of FIG. 2, according to the invention;

FIG. 3C is a schematic view of one embodiment of a proximal portion ofthe lead body of FIG. 2, a lead extension, and the control module ofFIG. 2, the lead extension configured and arranged to couple the leadbody to the control module, according to the invention;

FIG. 4 is a schematic top view of one embodiment of electrodes disposedon a paddle body, according to the invention;

FIG. 5A is a schematic top view of one embodiment of an enhancedelectrode with a plurality of longitudinally-extending grooves, theenhanced electrode suitable for use in an electrical stimulation system,according to the invention;

FIG. 5B is a schematic perspective view of one embodiment of theenhanced electrode of FIG. 5A, according to the invention;

FIG. 5C is a schematic end view of one embodiment of the enhancedelectrode of FIG. 5A, according to the invention;

FIG. 6A is a schematic top view of one embodiment of an enhancedelectrode with a plurality of laterally-extending grooves, the enhancedelectrode suitable for use in an electrical stimulation system,according to the invention;

FIG. 6B is a schematic perspective view of one embodiment of theenhanced electrode of FIG. 6A, according to the invention;

FIG. 7A is a schematic top view of one embodiment of an enhancedelectrode with a plurality of longitudinally-extending,rectangular-shaped grooves, the enhanced electrode suitable for use inan electrical stimulation system, according to the invention;

FIG. 7B is a schematic end view of one embodiment of the enhancedelectrode of FIG. 7A, according to the invention;

FIG. 8A is a schematic top view of one embodiment of an enhancedelectrode with a plurality of dimples, the enhanced electrode suitablefor use in an electrical stimulation system, according to the invention;

FIG. 8B is a schematic perspective view of one embodiment of theenhanced electrode of FIG. 8A, according to the invention;

FIG. 8C is a schematic end view of one embodiment of the enhancedelectrode of FIG. 8A, according to the invention;

FIG. 9A is a schematic perspective view of one embodiment of a distalend of a percutaneous lead that includes enhanced electrodes withlinearly-extending grooves, according to the invention;

FIG. 9B is a schematic perspective view of one embodiment of one of theenhanced electrodes of the lead of FIG. 9A, according to the invention;

FIG. 10A is a schematic perspective view of one embodiment of a distalend of a percutaneous lead that includes enhanced electrodes withnon-linearly-extending grooves, according to the invention;

FIG. 10B is a schematic perspective view of one embodiment of one of theenhanced electrodes of the lead of FIG. 10A, according to the invention;

FIG. 11A is a schematic perspective view of one embodiment of a distalend of a percutaneous lead that includes enhanced electrodes withdimples, according to the invention;

FIG. 11B is a schematic perspective view of one embodiment of one of theenhanced electrodes of the lead of FIG. 11A, according to the invention;

FIG. 12A is a schematic perspective view of one embodiment of a distalend of a percutaneous lead that includes enhanced segmented electrodeswith grooves, according to the invention;

FIG. 12B is a schematic perspective view of one embodiment of one of theenhanced segmented electrodes of the lead of FIG. 12A, according to theinvention;

FIG. 13A is a schematic perspective view of one embodiment of a distalend of a percutaneous lead that includes enhanced segmented electrodeswith dimples, according to the invention;

FIG. 13B is a schematic perspective view of one embodiment of one of theenhanced segmented electrodes of the lead of FIG. 13A, according to theinvention; and

FIG. 14 is a schematic overview of one embodiment of components of astimulation system, including an electronic subassembly disposed withina control module, according to the invention.

DETAILED DESCRIPTION

The present invention is directed to the area of implantable electricalstimulation systems and methods of making and using the systems. Thepresent invention is also directed to implantable electrical stimulationleads that include electrodes with enhanced outer surfaces, as well asmethods of making and using the electrical stimulation leads,electrodes, and electrical stimulation systems.

Suitable implantable electrical stimulation systems include, but are notlimited to, an electrode lead (“lead”) with one or more electrodesdisposed on a distal end of the lead and one or more terminals disposedon one or more proximal ends of the lead. Leads include, for example,deep brain stimulation leads, percutaneous leads, paddle leads, and cuffleads. Examples of electrical stimulation systems with leads are foundin, for example, U.S. Pat. Nos. 6,181,969; 6,516,227; 6,609,029;6,609,032; and 6,741,892; 7,244,150; 7,672,734; 7,761,165; 7,949,395;7,974,706; 8,175,710; 8,224,450; 8,364,278; and U.S. Patent ApplicationPublication No. 2007/0150036, all of which are incorporated byreference.

FIG. 1 illustrates schematically one embodiment of an electricalstimulation system 100. The electrical stimulation system includes acontrol module (e.g., a stimulator or pulse generator) 102, a paddlebody 104, and one or more lead bodies 106 coupling the control module102 to the paddle body 104. The paddle body 104 and the one or more leadbodies 106 form a lead. The paddle body 104 typically includes an arrayof electrodes 134. The control module 102 typically includes anelectronic subassembly 110 and an optional power source 120 disposed ina sealed housing 114. In FIG. 1, two lead bodies 106 are shown coupledto the control module 102.

The control module 102 typically includes one or more connectorassemblies 144 into which the proximal end of the one or more leadbodies 106 can be plugged to make an electrical connection via connectorcontacts (e.g., 316 in FIG. 3A) disposed in the connector assembly 144and terminals (e.g., 310 in FIG. 3A) on each of the one or more leadbodies 106. The connector contacts are coupled to the electronicsubassembly 110 and the terminals are coupled to the electrodes 134. InFIG. 1, two connector assemblies 144 are shown.

The one or more connector assemblies 144 may be disposed in a header150. The header 150 provides a protective covering over the one or moreconnector assemblies 144. The header 150 may be formed using anysuitable process including, for example, casting, molding (includinginjection molding), and the like. In addition, one or more leadextensions 324 (see FIG. 3C) can be disposed between the one or morelead bodies 106 and the control module 102 to extend the distancebetween the one or more lead bodies 106 and the control module 102.

It will be understood that the electrical stimulation system can includemore, fewer, or different components and can have a variety of differentconfigurations including those configurations disclosed in theelectrical stimulation system references cited herein. For example,instead of a paddle body 104, the electrodes 134 can be disposed in anarray at or near the distal end of a lead body 106′ forming apercutaneous lead, as illustrated in FIG. 2. The percutaneous lead maybe isodiametric along the length of the lead body 106″. The lead body106′ can be coupled with a control module 102′ with a single connectorassembly 144.

The electrical stimulation system or components of the electricalstimulation system, including one or more of the lead bodies 106, thecontrol module 102, and, in the case of a paddle lead, the paddle body104, are typically implanted into the body of a patient. The electricalstimulation system can be used for a variety of applications including,but not limited to, spinal cord stimulation, brain stimulation, neuralstimulation, muscle stimulation, and the like.

The electrodes 134 can be formed using any conductive, biocompatiblematerial. Examples of suitable materials include metals, alloys,conductive polymers, conductive carbon, and the like, as well ascombinations thereof. In at least some embodiments, one or more of theelectrodes 134 are formed from one or more of: platinum, platinumiridium, palladium, titanium, or rhenium.

The number of electrodes 134 in the array of electrodes 134 may vary.For example, there can be two, three, four, five, six, seven, eight,nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen, or moreelectrodes 134. As will be recognized, other numbers of electrodes 134may also be used. As will be recognized, other numbers of electrodes 134may also be used. In FIG. 1, sixteen electrodes 134 are shown. Theelectrodes 134 can be formed in any suitable shape including, forexample, round, oval, triangular, rectangular, pentagonal, hexagonal,heptagonal, octagonal, or the like.

The electrodes of the paddle body 104 or one or more lead bodies 106 aretypically disposed in, or separated by, a non-conductive, biocompatiblematerial including, for example, silicone, polyurethane, and the like orcombinations thereof. The paddle body 104 and one or more lead bodies106 may be formed in the desired shape by any process including, forexample, molding (including injection molding), casting, and the like.Electrodes and connecting wires can be disposed onto or within a paddlebody either prior to or subsequent to a molding or casting process. Thenon-conductive material typically extends from the distal end of thelead to the proximal end of each of the one or more lead bodies 106. Thenon-conductive, biocompatible material of the paddle body 104 and theone or more lead bodies 106 may be the same or different. The paddlebody 104 and the one or more lead bodies 106 may be a unitary structureor can be formed as two separate structures that are permanently ordetachably coupled together.

Terminals (e.g., 310 in FIG. 3A) are typically disposed at the proximalend of the one or more lead bodies 106 for connection to correspondingconductive contacts (e.g., 316 in FIG. 3A) in connector assemblies(e.g., 144 in FIG. 1) disposed on, for example, the control module 102(or to other devices, such as conductive contacts on a lead extension,an operating room cable, a splitter, an adaptor, or the like).

Conductive wires (not shown) extend from the terminals (e.g., 310 inFIG. 3A) to the electrodes 134. Typically, one or more electrodes 134are electrically coupled to a terminal (e.g., 310 in FIG. 3A). In someembodiments, each terminal (e.g., 310 in FIG. 3A) is only coupled to oneelectrode 134.

The conductive wires may be embedded in the non-conductive material ofthe lead or can be disposed in one or more lumens (not shown) extendingalong the lead. In some embodiments, there is an individual lumen foreach conductive wire. In other embodiments, two or more conductive wiresmay extend through a lumen. There may also be one or more lumens (notshown) that open at, or near, the proximal end of the lead, for example,for inserting a stylet rod to facilitate placement of the lead within abody of a patient. Additionally, there may also be one or more lumens(not shown) that open at, or near, the distal end of the lead, forexample, for infusion of drugs or medication into the site ofimplantation of the paddle body 104. The one or more lumens may,optionally, be flushed continually, or on a regular basis, with saline,epidural fluid, or the like. The one or more lumens can be permanentlyor removably sealable at the distal end.

As discussed above, the one or more lead bodies 106 may be coupled tothe one or more connector assemblies 144 disposed on the control module102. The control module 102 can include any suitable number of connectorassemblies 144 including, for example, two three, four, five, six,seven, eight, or more connector assemblies 144. It will be understoodthat other numbers of connector assemblies 144 may be used instead. InFIG. 1, each of the two lead bodies 106 includes eight terminals thatare shown coupled with eight conductive contacts disposed in a differentone of two different connector assemblies 144.

FIG. 3A is a schematic side view of one embodiment of a plurality ofconnector assemblies 144 disposed on the control module 102. In at leastsome embodiments, the control module 102 includes two connectorassemblies 144. In at least some embodiments, the control module 102includes four connector assemblies 144. In FIG. 3A, proximal ends 306 ofthe plurality of lead bodies 106 are shown configured and arranged forinsertion to the control module 102. FIG. 3B is a schematic side view ofone embodiment of a single connector assembly 144 disposed on thecontrol module 102′. In FIG. 3B, the proximal end 306 of the single leadbody 106′ is shown configured and arranged for insertion to the controlmodule 102′.

In FIGS. 3A and 3B, the one or more connector assemblies 144 aredisposed in the header 150. In at least some embodiments, the header 150defines one or more ports 304 into which the proximal end(s) 306 of theone or more lead bodies 106/106′ with terminals 310 can be inserted, asshown by directional arrows 312, in order to gain access to theconnector contacts disposed in the one or more connector assemblies 144.

The one or more connector assemblies 144 each include a connectorhousing 314 and a plurality of connector contacts 316 disposed therein.Typically, the connector housing 314 defines a port (not shown) thatprovides access to the plurality of connector contacts 316. In at leastsome embodiments, one or more of the connector assemblies 144 furtherincludes a retaining element 318 configured and arranged to fasten thecorresponding lead body 106/106′ to the connector assembly 144 when thelead body 106/106′ is inserted into the connector assembly 144 toprevent undesired detachment of the lead body 106/106′ from theconnector assembly 144. For example, the retaining element 318 mayinclude an aperture through which a fastener (e.g., a set screw, pin, orthe like) may be inserted and secured against an inserted lead body106/106′.

When the one or more lead bodies 106/106′ are inserted into the one ormore ports 304, the connector contacts 316 can be aligned with theterminals 310 disposed on the one or more lead bodies 106/106′ toelectrically couple the control module 102 to the electrodes (134 ofFIG. 1) disposed at a distal end of the one or more lead bodies 106.Examples of connector assemblies in control modules are found in, forexample, U.S. Pat. Nos. 7,244,150 and 8,224,450, which are incorporatedby reference.

In at least some embodiments, the electrical stimulation system includesone or more lead extensions. The one or more lead bodies 106/106′ can becoupled to one or more lead extensions which, in turn, are coupled tothe control module 102/102′. In FIG. 3C, a lead extension connectorassembly 322 is disposed on a lead extension 324. The lead extensionconnector assembly 322 is shown disposed at a distal end 326 of the leadextension 324. The lead extension connector assembly 322 includes acontact housing 328. The contact housing 328 defines at least one port330 into which a proximal end 306 of the lead body 106′ with terminals310 can be inserted, as shown by directional arrow 338. The leadextension connector assembly 322 also includes a plurality of connectorcontacts 340. When the lead body 106′ is inserted into the port 330, theconnector contacts 340 disposed in the contact housing 328 can bealigned with the terminals 310 on the lead body 106 to electricallycouple the lead extension 324 to the electrodes (134 of FIG. 1) disposedat a distal end (not shown) of the lead body 106′.

The proximal end of a lead extension can be similarly configured andarranged as a proximal end of a lead body. The lead extension 324 mayinclude a plurality of conductive wires (not shown) that electricallycouple the connector contacts 340 to terminal on a proximal end 348 ofthe lead extension 324. The conductive wires disposed in the leadextension 324 can be electrically coupled to a plurality of terminals(not shown) disposed on the proximal end 348 of the lead extension 324.In at least some embodiments, the proximal end 348 of the lead extension324 is configured and arranged for insertion into a lead extensionconnector assembly disposed in another lead extension. In otherembodiments (as shown in FIG. 3C), the proximal end 348 of the leadextension 324 is configured and arranged for insertion into theconnector assembly 144 disposed on the control module 102′.

It will be understood that the control modules 102/102′ can receiveeither lead bodies 106/106′ or lead extensions 324. It will also beunderstood that the electrical stimulation system 100 can include aplurality of lead extensions 224. For example, each of the lead bodies106 shown in FIGS. 1 and 3A can, alternatively, be coupled to adifferent lead extension 224 which, in turn, are each coupled todifferent ports of a two-port control module, such as the control module102 of FIGS. 1 and 3A.

Delivery of current to the electrodes causes charge (a product ofcurrent and pulse width) to flow through the electrodes. In some cases,in order to provide efficacious therapy to the patient, the currentreceived by patient tissue in proximity to the electrodes needs to bewithin a therapeutic range. When the current is below the therapeuticrange, the current may not be strong enough to provide efficacioustherapy. When the current is above the therapeutic range, one or moreill effects may occur to the patient (e.g., cell death, patientdiscomfort, undesired paresthesia, or the like).

Delivery of charge to the electrodes results in a charge density on theelectrodes. The charge density of a particular electrode is a result ofa number of different factors including, for example, the strength ofthe current, the pulse width of the current, the effective surface areaof the electrodes (e.g., the portion of the electrodes through whichcurrent flows to patient tissue), and the like. In at least someinstances, a high charge density may have unwanted results. For example,a high charge density at a platinum electrode may cause undesiredhydrogen bubbles to form at the electrodes. The hydrogen bubbles may beharmful to the patient. Additionally, the hydrogen bubbles may cause theelectrodes themselves to degrade or corrode, thereby causing decreasedor unpredictable performance of the electrical stimulation system, andpotentially requiring premature explantation of the electrode lead orstimulator.

It is often desirable to reduce the size of electrodes for a variety ofreasons, for example, patient comfort, ease of implantation, providingmore electrodes to offer more selectivity in choice of stimulation site,and the like. As electrode size decreases, the effective surface areaalso decreases, which typically results in higher charge density for agiven stimulation current. Additionally, as the number of stimulationchannels is increased in implantable control modules, the number ofelectrodes disposed on the leads that couple to these devices can,likewise, be increased. The leads (e.g., paddle leads, percutaneousleads, or the like), however, are often formed to be the physical samesize, despite an increase in the number of electrodes disposed on theleads. Consequently, the physical sizes of the electrodes can be reducedto accommodate the greater number of electrodes disposed on the samephysical lead space. Reducing the physical size of the electrodes mayincrease current densities passing through the smaller electrodes. Toaddress these issues, it may be possible to reduce the charge density ofthe one or more electrodes without increasing electrode size, byincreasing the surface area of the one or more of the electrodes.

Many conventional electrodes have outer surfaces that are relativelyflat and featureless. As described herein, enhanced electrodes can bemade which have effective surface areas that are greater than thecorresponding surface area of a similarly-sized flat-surfaced electrode.In at least some embodiments, the outer surfaces of the enhancedelectrodes define one or more indentations, one or more protrusions, acombination of indentations and protrusions, or other features whichincrease the effective surface area of the enhanced electrodes.

It will be understood that enhanced electrodes may be used with anysuitable lead of an electrical stimulation system (e.g., paddle leads,percutaneous leads, cuff leads, deep brain stimulation leads,microstimulators, or the like). Additionally, it will be understood thatenhanced electrodes may be formed into any suitable shape (e.g.,rectangular, oval, round, ring, segmented ring, tip, cuff, or the like)for use with different types of leads or electrical stimulation systems.

In at least some embodiments, enhanced electrodes may be disposed on apaddle lead. FIG. 4 is a schematic top view of one embodiment of adistal end of a paddle lead 400. The paddle lead 400 includes a paddlebody 402 and one or more lead bodies 404 extending from the paddle body402. The paddle body 402 includes a plurality of enhanced electrodes,such as enhanced electrode 406, formed on the paddle body 402.Conductors (not shown for clarity) extend from the enhanced electrodes406 and along the one or more lead bodies 404. In at least someembodiments, each of the enhanced electrodes 406 are configured andarranged for coupling with the control module 102. In at least someembodiments, the control module 102 includes a programmable stimulationchannel for each of the enhanced electrodes 406. For example, theillustrated paddle lead 400 includes 32 enhanced electrodes 406,arranged in four columns, that are configured and arranged to couplewith the control module 102, which has 32 programmable stimulationchannels.

The paddle lead 400 can include any number of enhanced electrodes 406including, for example, one, two, three, four, five, six, seven, eight,nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen,eighteen, twenty, twenty-two, twenty-four, twenty-six, twenty-eight,thirty, thirty-two, thirty-four, thirty-six, thirty-eight, forty,forty-two, forty-four, forty-six, forty-eight, fifty, fifty-two,fifty-four, fifty-six, fifty-eight, sixty-sixty-two, sixty-four, or moreenhanced electrodes 406. In FIG. 4, the paddle lead 400 is shown havingthirty-two electrodes. It will be understood that other numbers ofenhanced electrodes 406 may be used instead.

The enhanced electrodes 406 may be disposed on the paddle lead 400 inany suitable arrangement to provide therapy to a patient. In at leastsome embodiments, and as shown in FIG. 4, the enhanced electrodes 406are arranged into columns. The enhanced electrodes 406 can be arrangedinto any number of columns including, for example, two, three, four,five, six, seven, eight, or more columns. In FIG. 4, the paddle lead 400is shown having four columns. In at least some embodiments, each of thecolumns includes eight enhanced electrodes 406. It will be understoodthat other numbers of enhanced electrodes 406, either fewer or greater,may be disposed in each column. For example, at least one of the columnsmay include one, two, three, four, five, six, seven, eight, nine, ten,eleven, twelve, thirteen, fourteen, fifteen, sixteen, seventeen,eighteen, nineteen, twenty, or more enhanced electrodes 406. In at leastsome embodiments, at least one of the columns includes a differentnumber of enhanced electrodes 406 than at least one of the othercolumns.

The conductors (not shown) extending along the lead bodies 404 aretypically configured and arranged to couple to one or more connectors(e.g., on a control module, a lead extension, or the like) via terminalsdisposed on a proximal end of one or more of the lead bodies 404. In atleast some embodiments, conductive wires extending from the enhancedelectrodes 406 can be arranged into a plurality of distinct groupings,and each grouping disposed in a different one of the one or more leadbodies 404. In at least some embodiments, each of the one or more leadbodies 404 is configured and arranged for direct insertion into the oneor more connectors.

FIGS. 5A-8B show several different embodiments of enhanced electrodes406 a-d suitable for use with the paddle lead 400. Each of theembodiments shown in FIG. 5A-8B includes a plurality of indentationsdefined along the outer surfaces of the enhanced electrodes. Theindentations increase the effective surface area of the enhancedelectrodes such that the surface area of the enhanced electrode isgreater than the corresponding surface area of a similarly-sizedelectrode with a relatively flat surface area.

As described herein, increasing the effective surface area of theelectrodes can reduce the charge density on the electrodes when a givencurrent is provided to the electrodes. The charge density is equal tothe charge provided to the electrode divided by the effective surfacearea of the electrode. Thus, by increasing the effective surface area ofthe electrode, the charge density on the actual exposed surface of theelectrode can be reduced. Accordingly, by providing indentations orother surface textures along the effective surface area of the enhancedelectrodes, an increased surface area may be achieved without acorresponding increase in the overall physical dimensions (e.g., length,width, diameter, or the like) of the enhanced electrodes. Additionally,increasing the effective surface area of the enhanced electrodes mayalso reduce the resistance to electrical current flowing through theenhanced electrodes. In at least some instances, reducing the overallphysical dimensions of the electrodes can increase resistance to thedelivered stimulation through the electrodes, which may be an issue withsome implantable pulse generators.

In at least some embodiments, enhanced electrodes may be able to deliverhigher currents to patient tissue than similarly-sized electrodes withflat outer surfaces without exceeding a charge density that mayotherwise cause degradation or corrosion of the electrode or otherunwanted or deleterious effects. Additionally, in at least someembodiments, enhanced electrodes may be able to maintain the same chargedensity as a flat-surfaced electrode, while being formed with smalleroverall physical dimensions than the flat-surfaced electrode.

Enhanced electrodes may include any suitable type of indentationincluding, for example, grooves, dimples, cracks, fissures, notches,dents, depressions, gouges, incisions, nicks, clefts, gaps, mills, ruts,scores, cuts, trenches, scratches, channels, knurls, or the like orcombinations thereof. In at least some embodiments, enhanced electrodesmay include one or more projections to increase the surface area of theelectrodes. Any suitable projections may be used including, for example,one or more knobs, ridges, features, domes, bulges, juts, outthrusts,spurs, shelves, protuberances, or the like or combinations thereof.

Enhanced electrodes may include any suitable number of indentationsincluding, for example, one, two, three, four, five, six, seven, eight,nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen,seventeen, eighteen, nineteen, twenty, twenty-five, thirty, thirty-five,forty, forty-five, fifty, sixty, seventy, eighty, ninety, one hundred,two hundred, five hundred, or more indentations.

Indentations can be formed along the outer surface of enhancedelectrodes using any suitable method of manufacture including, forexample, electric discharge machining, stamping, laser machining,etching, knurling, application of one or more surface coatings onto theouter surface, roughing of the outer surface, or the like orcombinations thereof.

FIG. 5A is a schematic top view of one embodiment of the enhancedelectrode 406 a. FIG. 5B is a schematic perspective view of oneembodiment of the enhanced electrode 406 a. FIG. 5C is a schematic endview of one embodiment of the enhanced electrode 406 a. The enhancedelectrode 406 a includes a body 502 and an outer surface 504 of the body502. The outer surface 504 defines a plurality of grooves, such asgroove 506, extending at least partially along the outer surface 504.The body 502 has a length 508, a width 510, and a thickness 512.

In at least some embodiments, the enhanced electrode 406 a includes oneor more side walls, such as side wall 514. The one or more side walls514 can be used to anchor the enhanced electrode 406 a in the paddlebody 402 by extending at least a portion of the one or more side walls514 into the material of the paddle body 402. In at least someembodiments, at least one of the one or more side walls 514 defines oneor more anchoring apertures, such as anchoring aperture 516. In at leastsome embodiments, during manufacturing of the lead, the material of thepaddle body 402 can be flowed through the one or more anchoringapertures 516 and allowed to cure, thereby anchoring the enhancedelectrode 406 a in the paddle body 402.

In at least some embodiments, the grooves 506 extend longitudinally,such that the grooves 506 are parallel with the length 508 of theenhanced electrode 406 a. It will be understood that the grooves 506 canextend along the outer surface 504 in any suitable direction (e.g.,longitudinally, laterally, diagonally, obliquely, and the like). Thegrooves 506 may have any suitable length. In at least some embodiments,each of the grooves 506 has the same length. In at least someembodiments, at least one of the grooves 506 has a length that isdifferent from at least one of the other grooves 506. In at least someembodiments, at least one of the grooves 506 extends entirely across thelength 508 (or width 510) of the outer surface 504. In at least someembodiments, at least one of the grooves 506 extends no more than 90%,80%, 70%, 60% across the length 508 (or width 510) of the outer surface504.

The grooves 506 may have any suitable widths. In at least someembodiments, the grooves 506 have widths that are no greater than 25 μm,50 μm, 75 μm, 100 μm, 125 μm, 150 μm, 175 μm, 200 μm, or more. In atleast some embodiments, the widths of one or more of the grooves 506 areequal to the thickness 512 of the body 502 of the enhanced electrode 406a. In at least some embodiments, each of the grooves 506 has a similarwidth. In at least some embodiments, at least one of the grooves 506 hasa width that is different from at least one of the other grooves 506.

The grooves 506 can have any suitable cross-sectional shape along one ormore axes perpendicular to the outer surface 504. In at least someembodiments, the grooves 506 have a cross-sectional shape along one ormore axes perpendicular to the outer surface 504 that is semi-circular.It will be understood that the grooves 506 can have othercross-sectional shapes (e.g., rounded, rectangular, triangular, or thelike) along one or more axes perpendicular to the outer surface 504, asdescribed below with reference to FIGS. 7A-7B.

The grooves 506 can have any suitable depth. In at least someembodiments, the grooves 506 have depths that are no greater thanthree-fourths, two-thirds, one-half, one-third, or one-fourth of thewidth of the grooves 506. In at least some embodiments, the depths ofthe grooves 506 are no greater than three-fourths, two-thirds, one-half,one-third, or one-fourth of the thickness 512 of the body 502 of theenhanced electrode 406 a. In at least some embodiments, one or more ofthe grooves 506 extend radially inward from the outer surface 504. In atleast some embodiments, one or more of the grooves 506 extend in adirection that is perpendicular to the outer surface 504. In at leastsome alternate embodiments, one or more of the grooves 506 extend intothe enhanced electrode in a direction that is not perpendicular to theouter surface 504.

Any suitable spacing can be used between adjacent grooves 506. In atleast some embodiments, adjacent grooves 506 abut one another. In atleast some embodiments, the portions of the outer surface 504 disposedbetween adjacent grooves 506 are flat. In at least some embodiments, theentire outer surface 504 not containing one of the grooves 506 is flat.

In at least some embodiments, the grooves 506 extend laterally. FIG. 6Ais a schematic top view of one embodiment of the enhanced electrode 406b with the grooves 506 extending laterally, such that the grooves 506are parallel with the width 510 of the electrode. FIG. 6B is a schematicperspective view of one embodiment of the enhanced electrode 406 b. Inat least some embodiments, at least one of the grooves 506 extends in adirection that is different from at least one of the other grooves 506.

In at least some embodiments, the enhanced electrode 406 b includes oneor more side walls, such as side wall 514. The one or more side walls514 can be used to anchor the enhanced electrode 406 b in the paddlebody 402 by extending at least a portion of the one or more side walls514 into the material of the paddle body 402. In at least someembodiments, at least one of the one or more side walls 514 defines oneor more anchoring apertures, such as anchoring aperture 516. In at leastsome embodiments, during manufacturing of the lead, the material of thepaddle body 402 can be flowed through the one or more anchoringapertures 516 and allowed to cure, thereby anchoring the enhancedelectrode 406 b in the paddle body 402.

In FIGS. 5A-6B the grooves 506 are shown extending linearly (i.e., instraight lines). It will be understood that, in at least someembodiments, the grooves 506 can extend non-linearly (e.g., curved,wavy, swirled, zigzagged, spiraled, looped, FIG. 8, C-shaped, or thelike) such that the grooves 506 do not form a straight line. In at leastsome embodiments, all of the grooves 506 extend non-linearly. In atleast some embodiments, at least one of the grooves 506 extends linearlyand at least one of the grooves 506 extends non-linearly.

The grooves 506 can have any suitable cross-sectional shape along one ormore axes perpendicular to the outer surface 504 including, for example,semi-circular, rounded, rectangular, triangular, V-shaped, U-shaped, orthe like. In FIGS. 5A-6B, the grooves 506 are shown having asemi-circular cross-sectional shape along one or more axes perpendicularto the outer surface 504 (see e.g., FIG. 5C). FIG. 7A is a schematic topview of one embodiment of the enhanced electrode 406 c. FIG. 7B is aschematic end view of one embodiment of the enhanced electrode 406 c.The grooves 506 defined along the outer surface 504 of the enhancedelectrode 406 c have rectangular-shaped cross-sectional shapes along oneor more axes perpendicular to the outer surface 504.

In at least some embodiments, the enhanced electrode 406 c includes oneor more side walls, such as side wall 514. The one or more side walls514 can be used to anchor the enhanced electrode 406 c in the paddlebody 402 by extending at least a portion of the one or more side walls514 into the material of the paddle body 402. In at least someembodiments, at least one of the one or more side walls 514 defines oneor more anchoring apertures, such as anchoring aperture 516. In at leastsome embodiments, during manufacturing of the lead, the material of thepaddle body 402 can be flowed through the one or more anchoringapertures 516 and allowed to cure, thereby anchoring the enhancedelectrode 406 c in the paddle body 402.

As discussed above, any suitable indentation can be defined along theouter surface 504 of the enhanced electrode 406. In at least someembodiments, the outer surface 504 of the electrode 406 defines one ormore dimples. FIG. 8A is a schematic top view of one embodiment of theenhanced electrode 406 d. FIG. 8B is a schematic perspective view of oneembodiment of the enhanced electrode 406 d. FIG. 8C is a schematic endview of one embodiment of the enhanced electrode 406 d. The enhancedelectrode 406 d includes dimples, such as dimple 802, defined along theouter surface 504 of the enhanced electrode 406 d.

In at least some embodiments, the enhanced electrode 406 d includes oneor more side walls, such as side wall 514. The one or more side walls514 can be used to anchor the enhanced electrode 406 d in the paddlebody 402 by extending at least a portion of the one or more side walls514 into the material of the paddle body 402. In at least someembodiments, at least one of the one or more side walls 514 defines oneor more anchoring apertures, such as anchoring aperture 516. In at leastsome embodiments, during manufacturing of the lead, the material of thepaddle body 402 can be flowed through the one or more anchoringapertures 516 and allowed to cure, thereby anchoring the enhancedelectrode 406 d in the paddle body 402.

The dimples 802 can be arranged in any suitable linear or non-linearconfiguration (e.g., rows, columns, concentric circles, one or morepatterns, randomly, or the like) along the outer surface 504 of theenhanced electrode 406 d. In FIGS. 8A-8C, the dimples 802 are arrangedinto rows and columns. Any suitable number of dimples 802 can bedisposed along the outer surface 504 of the enhanced electrode 406 d.Any suitable spacing can be used between adjacent dimples 802. In atleast some embodiments, the space between adjacent dimples 802 is flat.In at least some embodiments, the entire outer surface 504 notcontaining one of the dimples 802 is flat. The dimples 802 can have anysuitable depth. In at least some embodiments, each of the dimples 802has a depth that is no more than one half of the thickness 512 of theenhanced electrode 406 d.

The dimples 802 can have any suitable shape along an axis parallel tothe outer surface 504 including, for example, round, oval, triangular,rectangular, diamond, star, asterisk, cruciform, pentagonal, hexagonal,heptagonal, octagonal, nonagonal, decagonal, or the like. In at leastsome embodiments, the dimples 802 have a non-geometric shape along anaxis parallel to the outer surface 504.

The dimples 802 can have any suitable diameter. In at least someembodiments, each of the dimples 802 has a diameter that is no greaterthan the thickness 512 of the enhanced electrode 406 d. In at least someembodiments, each of the dimples 802 has the same diameter. In at leastsome alternate embodiments, at least one of the dimples 802 has adiameter that is different from the diameter of at least one of theother dimples 802. In at least some embodiments, the dimpled outersurface 504 of the enhanced electrode 406 d has a surface area that istwice a surface area of a similarly-dimensioned electrode with a flatouter surface.

The dimples 802 can have any suitable cross-sectional shape along one ormore axes perpendicular to the outer surface 504. The dimples 802 shownin FIG. 8A-8C are formed as hemi-spherical dimples on the outer surface504. It will be understood that the dimples 802 can have anysuitably-shaped cross-sectional shape along one or more axesperpendicular to the outer surface 504 including, for example,semi-circular, semi-elliptical, rounded, rectangular, triangular,V-shaped, U-shaped, or the like. In at least some embodiments, thedimples 802 have a surface shape on the outer surface 504 that iscircular, rectangular, or triangular. In at least some embodiments, theenhanced electrode 406 d includes dimples 802 each having the samecross-sectional shape along one or more axes perpendicular to the outersurface 504. In at least some alternate embodiments, at least one of thedimples 802 has a cross-sectional shape along one or more axesperpendicular to the outer surface 504 that is different from thecorresponding cross-sectional shape of at least one of the other dimples802.

In at least some embodiments, the enhanced electrode 406 includes bothgrooves 506 and dimples 802. In at least some embodiments, the enhancedelectrode 406 includes one or more other types of indentations (e.g.,grooves, dimples, cracks, fissures, notches, dents, depressions, gouges,incisions, nicks, clefts, gaps, mills, ruts, scores, cuts, trenches,scratches, channels, or the like or combinations thereof) in lieu of, orin combination with, one or more grooves 506, one or more dimples 802,or one or more grooves 506 and one or more dimples 802.

Turning to FIGS. 9A-13B, enhanced electrodes may also be used with leadsother than paddle leads. As mentioned above, in at least someembodiments, enhanced electrodes can be used with percutaneous leads(e.g., spinal cord stimulation leads), deep brain stimulation leads,cuff leads, or the like. In at least some embodiments, enhancedelectrodes can be formed as ring electrodes. The enhanced electrodesused in conjunction with percutaneous leads or deep brain stimulationleads have outer surfaces with increased surface areas fromsimilarly-sized ring electrodes with non-indented or non-projectingsurfaces.

In at least some embodiments, the enhanced electrodes used inconjunction with percutaneous leads or deep brain stimulation leadsdefine a plurality or indentations. In at least some embodiments, theenhanced electrodes used in conjunction with percutaneous leads or deepbrain stimulation leads include a plurality or projections. In at leastsome embodiments, the enhanced electrodes used in conjunction withpercutaneous leads or deep brain stimulation leads define a plurality orindentations and a plurality of projections.

In at least some embodiments, the enhanced electrodes are formed as ringelectrodes. FIG. 9A is a schematic perspective view of one embodiment ofa distal end of a percutaneous lead 900. The lead 900 includes a leadbody 902 and ring-shaped enhanced electrodes, such as enhanced electrode904, disposed axially along the lead body 902. Any suitable number ofenhanced electrodes 904 may be disposed on the lead 900. In at leastsome embodiments, the lead 900 includes at least eight, or at leastsixteen enhanced electrodes 904. In at least some embodiments, the lead900 include no more than sixteen, or no more than eight enhancedelectrodes 904.

The enhanced electrode 904 includes a plurality of indentations. In atleast some embodiments, the indentations include grooves. FIG. 9B is aschematic perspective view of one embodiment of one of the enhancedelectrodes 904. The enhanced electrode 904 includes a width 906, adiameter 908, a thickness 910, and an outer surface 912. The enhancedelectrode 904 defines grooves 914 defined along the outer surface 912.The sizes, shapes, depths, orientations, and arrangements of the grooves914 can be varied, as discussed above with regards to the electrode 406.It may be an advantage to form the grooves 914 such that the grooves 914extend in a direction that is parallel with the width 906 of theenhanced electrode 904, as shown in FIGS. 9A-9B. Forming the grooves 914to extend in a direction that is parallel with the width 906 of theenhanced electrode 904 may promote tissue adhesion.

As discussed above with reference to FIGS. 6A-6B, the grooves can extendalong the enhanced electrode linearly or non-linearly (e.g., curved,wavy, swirled, zigzagged, spiraled, looped, FIG. 8, C-shaped, or thelike) such that the grooves 506 do not form a straight line. FIG. 10A isa schematic perspective view of another embodiment of the distal end ofthe percutaneous lead 900. The lead 900 includes ring-shaped enhancedelectrodes, such as enhanced electrode 1004, disposed axially along thelead body 902.

FIG. 10B is a schematic perspective view of one embodiment of one of theenhanced electrodes 1004. The enhanced electrode 1004 includes the width906, the diameter 908, the thickness 910, and the outer surface 912. Theenhanced electrode 1004 defines grooves 914 defined along the outersurface 912. In FIGS. 10A-10B, the grooves 914 include waves 1006 andextend non-linearly (e.g., form curved lines, form non-straight lines,or the like) along the outer surface 912 of the enhanced electrode 1004.

In at least some embodiments, the indentations include dimples. FIG. 11Ais a schematic perspective view of another embodiment of the distal endof the percutaneous lead 900. The lead 900 includes ring-shaped enhancedelectrodes, such as enhanced electrode 1104, disposed axially along thelead body 902. FIG. 11B is a schematic perspective view of oneembodiment of one of the enhanced electrodes 1104. The enhancedelectrode 1104 includes the width 906, the diameter 908, the thickness910, and the outer surface 912. The enhanced electrode 1104 definesdimples, such as dimple 1106, defined in the outer surface 912. Thesizes, shapes, depths, orientations, and arrangements of the dimples1106 can be varied, as discussed above with regards to the electrode 406d, and with reference to FIGS. 8A-8C.

Turning now to FIGS. 12A-13B, in at least some embodiments, enhancedelectrodes may be formed as segmented electrodes. In at least someembodiments, the enhanced segmented electrodes are configured andarranged such that at least two enhanced segmented electrodes aredisposed circumferentially on one part of the lead body (i.e., along atransverse cross-section of the lead body). In at least someembodiments, at least three enhanced segmented electrodes are disposedon one part of the lead body of the lead body. In at least someembodiments, at least four enhanced segmented electrodes are disposed onone part of the lead body.

Segmented leads can be used with any suitable electrical stimulationsystems. In at least some embodiments, segmented leads are used for deepbrain stimulation. Deep brain stimulation devices and leads aredescribed in the art. See, for instance, U.S. Pat. No. 7,809,446; U.S.Patent Application Publications Nos. 2007/0150036; 2009/0187222;2009/0276021; 2010/0076535; and 2010/0268298; and U.S. patentapplication Ser. No. 12/177,823 (“Lead With Transition and Methods ofManufacture and Use”). Each of these references is incorporated hereinby reference in its respective entirety.

FIG. 12A is a schematic perspective view of another embodiment of thedistal end of the lead 900. The lead 900 includes enhanced segmentedelectrodes, such as enhanced electrode 1204, disposed axially along thelead body 902. FIG. 12B is a schematic perspective view of oneembodiment of one set of the enhanced segmented electrodes 1204. Theenhanced electrode 1204 defines grooves 1214 along the outer surface 912of the enhanced electrode 1204. The sizes, shapes, depths, orientations,and arrangements of the grooves 1214 can be varied, as discussed abovewith regards to the enhanced electrodes 406 and 904.

FIG. 13A is a schematic perspective view of another embodiment of thedistal end of the percutaneous lead 900. The lead 900 includes enhancedsegmented electrodes, such as enhanced electrode 1304, disposed axiallyalong the lead body 902. FIG. 13B is a schematic perspective view of oneembodiment of one of the circumferential sets of enhanced segmentedelectrodes 1304. The enhanced segmented electrode 1304 defines dimples,such as dimple 1306, on the outer surface 912. The sizes, shapes,depths, orientations, and arrangements of the dimples 1306 can bevaried, as discussed above with regards to the electrodes 406 d and1104, and with reference to FIGS. 8A-8C and 11A-11B, respectively.

It will be understood that any of the indentations shown in FIGS. 9A-13Bcan be used in combination with one another. Moreover, any of theindentations shown in FIGS. 9A-13B can be used in combination with anyother suitable indentation or

FIG. 14 is a schematic overview of one embodiment of components of anelectrical stimulation system 1400 including an electronic subassembly1410 disposed within a control module. It will be understood that theelectrical stimulation system can include more, fewer, or differentcomponents and can have a variety of different configurations includingthose configurations disclosed in the stimulator references citedherein.

Some of the components (for example, power source 1412, antenna 1418,receiver 1402, and processor 1404) of the electrical stimulation systemcan be positioned on one or more circuit boards or similar carrierswithin a sealed housing of an implantable pulse generator, if desired.Any power source 1412 can be used including, for example, a battery suchas a primary battery or a rechargeable battery. Examples of other powersources include super capacitors, nuclear or atomic batteries,mechanical resonators, infrared collectors, thermally-powered energysources, flexural powered energy sources, bioenergy power sources, fuelcells, bioelectric cells, osmotic pressure pumps, and the like includingthe power sources described in U.S. Pat. No. 7,437,193, incorporatedherein by reference.

As another alternative, power can be supplied by an external powersource through inductive coupling via the optional antenna 1418 or asecondary antenna. The external power source can be in a device that ismounted on the skin of the user or in a unit that is provided near theuser on a permanent or periodic basis.

If the power source 1412 is a rechargeable battery, the battery may berecharged using the optional antenna 1418, if desired. Power can beprovided to the battery for recharging by inductively coupling thebattery through the antenna to a recharging unit 1416 external to theuser. Examples of such arrangements can be found in the referencesidentified above.

In one embodiment, current is emitted by the electrodes 134 on thepaddle or lead body to stimulate nerve fibers, muscle fibers, or otherbody tissues near the electrical stimulation system. A processor 1404 isgenerally included to control the timing and electrical characteristicsof the electrical stimulation system. For example, the processor 1404can, if desired, control one or more of the timing, frequency, strength,duration, and waveform of the pulses. In addition, the processor 1404can select which electrodes can be used to provide stimulation, ifdesired. In some embodiments, the processor 1404 may select whichelectrode(s) are cathodes and which electrode(s) are anodes. In someembodiments, the processor 1404 may be used to identify which electrodesprovide the most useful stimulation of the desired tissue.

Any processor can be used and can be as simple as an electronic devicethat, for example, produces pulses at a regular interval or theprocessor can be capable of receiving and interpreting instructions froman external programming unit 1408 that, for example, allows modificationof pulse characteristics. In the illustrated embodiment, the processor1404 is coupled to a receiver 1402 which, in turn, is coupled to theoptional antenna 1418. This allows the processor 1404 to receiveinstructions from an external source to, for example, direct the pulsecharacteristics and the selection of electrodes, if desired.

In one embodiment, the antenna 1418 is capable of receiving signals(e.g., RF signals) from an external telemetry unit 1406 which isprogrammed by a programming unit 1408. The programming unit 1408 can beexternal to, or part of, the telemetry unit 1406. The telemetry unit1406 can be a device that is worn on the skin of the user or can becarried by the user and can have a form similar to a pager, cellularphone, or remote control, if desired. As another alternative, thetelemetry unit 1406 may not be worn or carried by the user but may onlybe available at a home station or at a clinician's office. Theprogramming unit 1408 can be any unit that can provide information tothe telemetry unit 1406 for transmission to the electrical stimulationsystem 1400. The programming unit 1408 can be part of the telemetry unit1406 or can provide signals or information to the telemetry unit 1406via a wireless or wired connection. One example of a suitableprogramming unit is a computer operated by the user or clinician to sendsignals to the telemetry unit 1406.

The signals sent to the processor 1404 via the antenna 1418 and receiver1402 can be used to modify or otherwise direct the operation of theelectrical stimulation system. For example, the signals may be used tomodify the pulses of the electrical stimulation system such as modifyingone or more of pulse duration, pulse frequency, pulse waveform, andpulse strength. The signals may also direct the electrical stimulationsystem 1400 to cease operation, to start operation, to start chargingthe battery, or to stop charging the battery. In other embodiments, thestimulation system does not include an antenna 1418 or receiver 1402 andthe processor 1404 operates as programmed.

Optionally, the electrical stimulation system 1400 may include atransmitter (not shown) coupled to the processor 1404 and the antenna1418 for transmitting signals back to the telemetry unit 1406 or anotherunit capable of receiving the signals. For example, the electricalstimulation system 1400 may transmit signals indicating whether theelectrical stimulation system 1400 is operating properly or not orindicating when the battery needs to be charged or the level of chargeremaining in the battery. The processor 1404 may also be capable oftransmitting information about the pulse characteristics so that a useror clinician can determine or verify the characteristics.

The above specification, examples and data provide a description of themanufacture and use of the composition of the invention. Since manyembodiments of the invention can be made without departing from thespirit and scope of the invention, the invention also resides in theclaims hereinafter appended.

What is claimed as new and desired to be protected by Letters Patent ofthe United States is:
 1. A medical lead for providing electricalstimulation of patient tissue, the medical lead comprising: a lead bodyhaving a distal end portion, a proximal end portion, a circumference,and a longitudinal length; a plurality of electrodes disposed along thedistal end portion of the lead body, each of the plurality of electrodeshaving a width, a length, and an outer surface, wherein at least one ofthe plurality of electrodes is a segmented electrode that extends aroundless than the entire circumference of the lead body and that is also agrooved electrode that defines a plurality of grooves along the outersurface; a plurality of terminals disposed along the proximal endportion of the lead body; and a plurality of conductive wires couplingthe plurality of terminals to the plurality of electrodes.
 2. The leadassembly of claim 1, wherein the at least one grooved electrode has athickness, and each of the plurality of grooves defined along the atleast one grooved electrode has a depth, and wherein the depth of eachof the plurality of grooves defined along the at least one groovedelectrode is no more than one-half of the thickness of the at least onegrooved electrode.
 3. The lead assembly of claim 1, wherein theplurality of grooves defined along the at least one grooved electrodeare spaced-apart from one another such that the grooves do not abut oneanother.
 4. The lead assembly of claim 1, wherein an entire non-groovedportion of the outer surface of the at least one grooved electrode isflat.
 5. The lead assembly of claim 1, further comprising a surfacecoating disposed over at least a portion of the outer surface of the atleast one grooved electrode.
 6. The lead assembly of claim 1, whereinthe plurality of grooves are defined along the outer surfaces of each ofthe plurality of electrodes.
 7. The medical lead of claim 1, wherein theplurality of grooves extend non-linearly along the grooved electrodesuch that each of the plurality of grooves extends longitudinally in acurved line along the outer surface of the grooved electrode withrespect to the longitudinal length of the lead body.
 8. The leadassembly of claim 7, wherein the plurality of grooves extendlongitudinally in curved lines along the outer surface of the groovedelectrode with respect to the width of the grooved electrode.
 9. Thelead assembly of claim 7, wherein the plurality of grooves extendlongitudinally in curved lines along the outer surface of the groovedelectrode with respect to the length of the grooved electrode.
 10. Themedical lead of claim 1, wherein at least one groove of the plurality ofgrooves has one of a U-shaped cross-section or a V-shaped cross-sectionalong a plane that is perpendicular to the outer surface andperpendicular to a length of the at least one groove of the plurality ofgrooves.
 11. The medical lead of claim 1, wherein at least one groove ofthe plurality of grooves has a rectangular cross-sectional shape along aplane that is perpendicular to the outer surface and perpendicular to alength of the at least one groove of the plurality of grooves.
 12. Anelectrical stimulating system comprising: the lead assembly of claim 1;a control module configured and arranged to electrically couple to theproximal end portion of the lead body of the lead assembly, the controlmodule comprising a housing, and an electronic subassembly disposed inthe housing; and a connector configured and arranged for receiving thelead body, the connector comprising a connector housing defining atleast one port configured and arranged for receiving the proximal endportion of the lead body, and a plurality of connector contacts disposedin the at least one port, the plurality of connector contacts configuredand arranged to couple to the plurality of terminals when the proximalend portion of the lead body is received by the port.
 13. The leadassembly of claim 1, wherein the lead body is isodiametric.
 14. Amedical lead for providing electrical stimulation of patient tissue, themedical lead comprising: a lead body having a distal end portion, aproximal end portion, and a longitudinal length; a plurality ofelectrodes disposed along the distal end portion of the lead body, theplurality of electrodes each having an exterior surface and an opposinginterior surface, wherein the plurality of electrodes are configured andarranged such that when the lead is implanted in a patient the exteriorsurfaces of each of the plurality of electrodes are exposed to patienttissue and provide a surface along which stimulation energy propagatesfrom the lead to patient tissue, wherein at least one of the pluralityof electrodes is a grooved electrode, wherein a plurality of grooves aredefined along the exterior surface of the at least one grooved electrodeand extend non-linearly with each of the plurality of groove extendingin a curved line around less than an entire circumference of the lead,wherein the interior surface of the at least one grooved electrode isungrooved; a plurality of terminals disposed along the proximal endportion of the lead body; and a plurality of conductive wires couplingthe plurality of terminals to the plurality of electrodes.
 15. The leadassembly of claim 14, further comprising a paddle body disposed alongthe distal end portion of the lead body, wherein the at least onegrooved electrode is disposed on the paddle body.
 16. The lead assemblyof claim 15, wherein the at least one grooved electrode comprises atleast one side wall at least partially inset into the paddle body. 17.The lead assembly of claim 16, wherein the at least one groovedelectrode comprises at least one anchoring aperture defined in the atleast one side wall, the at least one anchoring aperture configured andarranged to receive a portion of the paddle body.
 18. The lead assemblyof claim 14, wherein the at least one grooved electrode is a ringelectrode.
 19. The medical lead of claim 14, wherein the plurality ofgrooves extend longitudinally with respect to the longitudinal length ofthe lead body across an entire length of the at least one groovedelectrode.
 20. The medical lead of claim 14, wherein the interiorsurface of the at least one grooved electrode is flat.